Grasper bar pivoting and positioning

ABSTRACT

Disclosed are means for pivoting and positioning the bobbin tube grasper bars of an automatic doffing apparatus with precision and in concert on both sides of a textile yarn processing machine, such as a spinning frame, such that tube grasper elements depending from said bars are precisely positionable in coaxial alignment with and above the spindle blades thereof for donning tubes thereon by gravitational free fall. Present means obviate the problems associated with a non-linear or otherwise skewed grasper bar due to an imbalance of diverse forces imposed at diverse points along the longitudinal length thereof, as frequently occurs in prior art constructions. Present means employs a single actuating means, such as a hydraulic piston and cylinder assembly, joined by linkages to move control shafts on both sides of the machine, the control shafts in turn being interconnected with each grasper bar lifting and pivoting mechanism spaced therealong by a bell crank and pivot lever. Further present means includes adjusting means for balancing all forces exerted on the grasper bar and adjusting its aforesaid position exactly by changing the pivot point position of each bell crank.

United States Patent [191 Pray et al.

1 1 GRASPER BAR PIVOTING AND POSKTIONING [75] inventors: Lester W. Pray; Gordon C.

Anderson, both of Clemson, SC.

[73] Assignee: Maremont Corporation, Chicago,

ill.

22 Filed: Apr. 30, 1973 21 Appl. No.: 355,605

Primary Examiner-John Petrakes Attorney, Agent, or Firm-Donald H. Feldman [451 Aug. 6, 1974 [5 7] ABSTRACT Disclosed are means for pivoting and positioning the bobbin tube grasper bars of an automatic doffing apparatus with precision and in concert on both sides of a textile yarn processing machine, such as a spinning frame, such that tube grasper elements depending from said bars are precisely positionable in coaxial alignment with and above the spindle blades thereof for donning tubes thereon by gravitational free fall. Present means obviate the problems associated with a non-linear or otherwise skewed grasper bar due to an imbalance of diverse forces imposed at diverse points along the longitudinal length thereof, as frequently occurs in prior art constructions. Present means employs a single actuating means, such as a hydraulic piston and cylinder assembly, joined by linkages to move control shafts on both sides of the machine, the control shafts in turn being interconnected with each grasper bar lifting and pivoting mechanism spaced therealong by a bell crank and pivot lever. Further present means includes adjusting means for balancing all forces exerted on the grasper bar and adjusting its aforesaid position exactly by changing the pivot point position of each bell crank.

5 Claims, 4 Drawing Figures GRASPER BAR PIVOTING AND POSITIONING BACKGROUND OF THE INVENTION This invention relates to automatic doffing and donning apparatus for bobbin tubes, such as is disclosed in U.S. Pat. 3,786,621, entitled Grasper Bar Positioning Mechanism for Automatic Doffer, of common assignee hereto, and is an improvement thereon.

Textile yarn processing machines employing doffers of this type, such as spinning frames, commonly have two rows of yarn processing stations extending longitudinally the length of each side of the machine. In the process of removing or doffmg full bobbin tube packages of yarn from such processing stations and replacing them or donning such stations with empty bobbin tubes for subsequent processing of yet more yarn, usually the processing stations in both rows are ready for doffing and donning at exactly the same time. Thus, the advantages present in a simultaneous doffing and donning of both rows are manifest in an increased efficiency of machine usage.

Efficiency also has been enhanced through the use of a control system which permits the donning of empty bobbin tubes upon spindles of the processing stations by free fall thereof by gravity, as is disclosed in U.S. Pat. 3,751,895 entitled Method and Apparatus for Donning Bobbins, also of common assignee.

A problem common to the efficacious usage of both concepts resides in a capability to precisely align the grasper bar holding the tube grasper elements such that it is precisely parallel a line intersecting and normal to the vertical axes of the spindles in each row thereof.

Failing such precise alignment, such as by a skewing of the grasper bar and/or its non-linearity, in release of the empty. bobbin tubes for free fall towards the spindles the tubes may miss the spindles completely, or hit the spindles obliquely and rebound or fail to seat themselves fully upon the spindles. At the least, these circumstances result in an inoperative yarn processing station which requires manual correction mitigating against the value and purpose of using an automatic doffer; beyond this, tube misses and rebounds can result in the tube being cast into the innards of the machine resulting in damage thereto, or being cast outwardly the machine into the aisle creating a hazard to any person passing through the aisle, or even into the innards of an adjacent machine across the aisle damaging it and its moving parts.

In apparatuses of the type herein described, the problem and difficulties mentioned are acute in that the extremely precise alignment required of the grasper bar is most difficult to attain. This problem is yet further aggravated when one attempts to coordinate the positionings and motions of the lifter mechanisms and their interconnected grasper bars on both sides of the machine so that they act simultaneously and position themselves with great precision. Prior attempts have involved the use of complex and numerous subassemblies interconnected functionally for effecting coordinate moving and positioning, and yet withal such attempts have not proved to be satisfactory and reliable but rather have even further aggravated the problemby the application of unbalanced forces to the lifter mechanisms to skew or otherwise distort the grasper bar out of linearity and thus prevent vertical coaxial alignment of all grasper elements thereon with the corresponding spindles thereunder at the process step of donning tubes .onto the spindle blades.

OBJECTS OF THE INVENTION It is to the remedy of the aforesaid problem and its attendant difficulties that the present invention is directed, such being an object thereof.

Thus, an object of the invention is to provide simple, reliable and economic means for the simultaneous and coordinate lateral movement and positioning of a plurality of bobbin tube grasper bars relative to and on both sides of a textile yarn processing machine.

Yet other desirable objects of this invention will become apparent from and/or are inherent in the following descriptions and explanations.

SUMMARY OF THE INVENTION The present invention provides for the aforesaid lateral pivoting and positioning of the grasper bars by employing an actuating means which produces a prescribed and predetermined linear movement, translating means which translates said movement into pivotal rotation of levers on both sides of the textile machine and such pivotal movement in turn into a corresponding prescribed and predetermined linear movement of two control shafts, one on each side of the machine, which control shafts in turn are interconnected with a plurality of pivoting assemblies each including a bell crank lever to convert such latter linear movement into an angular movement of support and lifter mechanisms and their interconnected grasper bars laterally toward and away from their respective sides of the machine into precise positions relative thereto. The present invention also provides adjusting means for adjusting the pivot points of the bell crank levers for in turn adjusting said angular movement of the lifter support mechanisms and associated portions of their interconnected grasper bars and the precise positions of the latter relative the machine such that depending grasper elements on the grasper bars are alignable vertically coaxial with and above spindles of the machine.

In particular, a single actuating means may be used to actuate coordinate and simultaneous pivotings and positionings of grasper bars on both sides of the machine, such as a hydraulic or pneumatic cylinder and rod and piston assembly, or a screw thread device interconnected by gearing to some control device or system, such as has been disclosed in the aforesaid U.S. Pat. Nos. 3,786,621 and 3,751,895. The translating means may comprise, as in the preferred embodiment hereinafter described in detail, a clevis attached to the end of the rod or screw thread interconnected with levers on either side of the machine through a rotatable shaft or sleeve therebetween, and the levers in turn pivotally connected with the control shafts to move the latter linearly the precise chordal distance: of lever pivotings. At diverse points along the shafts corresponding to points of interconnection of the support lifter mechanisms with the associated grasper bars, the shafts are interconnected with a bell crank lever, the position of the pivot point of which prescribes the exact positioning of that portion of the respective grasper bar corresponding thereto relative the machine. Ajustment of such pivot points is simply effected, according to the invention, by the linear displacement of anchor plates attached thereto.

DESCRIPTION OF THE DRAWINGS A fuller understanding of the invention and its attendant advantages and features will be in part evident from and in part pointed out from the following description of a preferred embodiment thereof and its operation, which should be read in conjunction with the accompanying drawings, in which:

FIG. 1 is a fragmentary and partially schematic side elevational view of one side of a textile yarn spinning frame equipped with an automatic doffer apparatus embodying the invention;

FIG. 2 is a fragmentary top plan view of the bobbin tube conveyors on both sides of the machine and the present translating and the actuating means of the invention;

FIG. 3 is an enlarged fragmentary and foreshortened elevational view in partial section, taken generally along line 33 of FIG. 2, showing a portion of the present translating means and of the present pivoting assembly including the bell crank lever and adjusting means thereof; and

FIG. 4 is a fragmentary elevational view taken along line 4-4 of FIG. 3, showing interconnections between the support lifter mechanism and the present pivoting assembly.

PREFERRED EMBODIMENT In FIG. 1, the spinning frame generally designated is of conventional construction, having two rows of yarn processing stations extending between end cabinets 12 and 14 longitudinally the machine 10 on either side of the frame, one side only being shown. Each row includes a spindle rail 16 upon which is mounted a plurality of spindle assemblies, one per yam-processing station, and a vertically reciprocable ring rail 18 bearing thereon spinning rings 19 each of which encircles a spindle assembly. Each spindle assembly includes a vertically upstanding spindle blade upon which is seated, as shown, a yarn-filled bobbin tube 20. Other conventional components of the yarn processing stations include for each a set of yarn drafting and delivery rolls at an elevation above the spindle blades and their associated bobbin tubes 20 and yarn delivery means usually in the form of a creel for supplying roving to the sets of rolls and at an elevation thereabove, such other components not being shown.

Extending longitudinally parallel each side of machine 10 and its row of yarn processing stations is an automatic bobbin tube doffing and donning apparatus, generally designated 22. Apparatus 22 comprises an elongate grasper bar 24 bearing dependent bobbin tube grasper elements 26; a bobbin tube conveyor means generally designated 28 for removing yarn-filled bobbin tubes 20 once they have been doffed to a place of storage or transfer to other machines and for supplying empty bobbin tubes 44 to positions for donning operatons of apparatus 22, conveyor means 28 bearing a movable tape 30 and a plurality of alternate conveyor pegs 32 for receiving yarn-filled tubes 20 and a similar plurality of alternate conveyor pegs 34 for supplying empty tubes 44 for donning operations; and a plurality of straight-line motion lifter mechanisms of the Scott Russell type generally designated 36 interconnected pivotally at their tops with bar 24 at diverse points therealong, and at their bottoms with machine 10 for effecting lateral pivoting movement of bar 24 toward and away from frame 10 and for raising and lowering bar 24 generally in accordance with the doffing and donning process described in detail in aforesaid U.S. Pat. Nos. 3,786,621 and 3,751,895. Essentially this process comprises the steps of (a) indexing tape 30 such that alternate empty pegs 32 are positioned beneath and in substantially vertical alignment with the spindle assemblies of the row thereof and the yarnfilled tubes 20 mounted thereupon; (b) pivoting bar 24 away from machine It), by pivoting mechanisms 36 attached thereto, a distance beyond the outwardly extending distance of rail 16; (c) raising bar 24 to an elevation above that of the tops of bobbin tubes 20 by longitudinally moving the bottom ends of the long arms 38 of mechanisms 36 toward the bottom ends of short arms 40 thereof in a scissors-type movement, such short arms 40 being interconnected with machine 10 such that there is no relative longitudinal movement of its bottom ends, and long arms 38 being interconnected with machine 10 such that one may effect the aforesaid relative longitudinal movement by so moving a longitudinally extending rod 42 to which at diverse points therealong the bottoms of long arms 38 are clamped, such as by brackets 41; (d) pivoting bar 24 toward frame 10 to align depending grasper elements 26 vertically coaxial with tubes 20 and the spindles upon which they are seated, by so pivoting the lower ends of mechanism 36; (e) lowering grasper bar 24 until grasper elements 26 fully enter the central orifices of respective tubes 20, by moving the bottoms of long arms 33 away from the bottoms of short arms 40; (f) inflating the elastic nipples of grasper elements until they firmly grip the interior walls of the central orifices of tubes 20; (g) raising bar 24 and with it tubes 20 until the bottoms of tubes 20 clear the tops of the spindle blades upon which they had been seated, by moving the bottoms of long arms 38 toward the bottoms of short arms 40; (h) moving bar 24 and with it tubes 20 away from machine 10 beyond the outwardly extending distance of rail 16, by so pivoting the bottoms of long and short arms 38 and 40; (i) lowering bar 24 and with it tubes 20 depending therefrom to an elevation wherein the bottoms of tubes 20 are above the elevation of the tops of pegs 32, by moving the bottoms of long arms 38 away from bottoms of arms 40; (j) moving bar 24 toward machine 10 until grasper elements 26 with their depending tubes 20 are vertically coaxial and above pegs 32, by pivoting the bottoms of arms 38 and 40; (k) deflating the nipples of elements 26 to release tubes 20 therefrom such that tubes 20 prior to full release vertically self-plumb and then upon full release fall vertically to seat themselves upon conveyor pegs 32 and tape 30; (l)-indexing tape 30 such that alternate conveyor pegs 34 (FIG. 2) and empty bobbin tubes 44 seated thereon are aligned vertically coaxial with grasper elements 26; (m) lowering grasper bar 24 until elements 26 fully enter the central orifices of tubes 44, by moving the bottoms of arms 38 away from arms 40; (n) inflating the nipples of elements 26 to grip tubes 44; (0) raising bar 24 and with it tubes 44 depending therefrom to an elevation such that the bottoms of tubes 44 clear the tops of pegs 34; (p) moving bar 24 away from frame 10 until depending tubes 44 are beyond the outwardly extending distance of rail 16, by so pivoting arms 38 and 40; (q) raising bar 24 to an elevation wherein the bottoms of tubes 44 depending therefrom are above the elevation of the tops of the spindle blades, by scissors action of mechanisms 36; (r) moving bar 24 toward machine It) until elements 26 are aligned vertically coaxial with the corresponding spindle blades and bar 26 is parallel a line normal to and intersecting the axes of such spindle blades, according to the present invention; deflating the nipples of elements 26 to release tubes 66 such that prior to full release tubes dd vertically self-plumb and upon full release fall vertically to seat themselves fully upon the corresponding spindle blades, thus to complete the tube doffing and donning operations; (t) pivoting bar 24% away from frame 10 a distance sufficient to clear rail 16; (u) lowering bar 24 to an elevation such that the bottoms of elements 26 are above the tops of tubes 29 on conveyor tape 30; (v) pivoting bar 24 toward frame it) until elements 26 depending therefrom are in vertical coaxial alignment with and above now empty pegs 3d; and finally (w) moving conveyor tape 36, pegs M and 32 and tubes 26 thereon to a tube discharge and loading device of apparatus 22 (not otherwise specifically shown), such as at end 12 of machine 16, which device removes tubes from tape and loads other empty tubes 44 onto pegs 34 for the next doffing-donning cycle.

The coordinate raising and lowering of grasper bars 26 on both sides of machine 10 are effected as disclosed in aforesaid U.S. Pat. No. 3,786,621, wherein movement of rods 42 controls the scissors actions of mechanisms 36, rods 42 being supported for longitudinal movement relative frame 10 by bearings 43 which are fixed to frame it) and being controlled to move in concert by hydraulic or other means known in the art.

The lateral movements of each grasper bar 24 toward and away from machine it) are effected by pivotings of mechanisms 36 as hereinbefore described and disclosed in greater detail in aforesaid Pat. No. 3,786,621. Means for effecting coordinate pivotings and precise positionings of grasper bars 24 simultaneously on both sides of machine it), the substance of the present invention, may be seen by reference to FIGS. 2 to 4.

According to the invention, a single pivotingactuating means is employed to effect coordinate pivotings and positionings of both grasper bars 24 as req d y aforesaid steps (j), (P) and (v) in a simultaneous manner and with precision on both sides of machine it). In FIG. 2, while the exemplified actuating means is shown as a cylinder i6 and a rod and piston 68 assembly, one knowledgeable in the art may employ other specific means for providing precise linear displacements as herein required. Cylinder 46 is pivotally anchored to a fixed member 50 by means of an anchor clevis 67.. The outer end of rod and piston 48 terminates in yet another clevis 52 so as to join them with the lower extending portion 54- of a downwardly depending lever arm 56. Affixed to the inner upper flanges 29 of conveyors 28 on each side of machine it) are a pair of opposing anchor plates 58, each having an upstanding flange 69 bored to receive therebetween each end of a rotatable sleeve 62 journalled therein for relative rotation and support. Lever arm 56 at its upper end is rigidly fixed to sleeve 62 for coordinate pivoting or rotation, and as aforesaid at its lower end is joined to clevis 52 by a pin 64; intermediate arm 56 it is pivotally connected with a control shaft 66 which latter extends longitudinally frame it and spaced inwardly of conveyor 28. On the opposite side, another lever arm 68 also is rigidly fixed to the other end of sleeve 62 for coordinate pivoting or rotation therewith, and at its lower end is pivotally connected to another control shaft 70 which latter is longitudinally disposed relative frame 10 and spaced inwardly of the other conveyor 28. Grasper bars 24 and their associated mechanisms 36 are interconnected with the respective shafts 66 and 76 through pivot assemblies generally designated 72, as shall now be described, such that displacements of the actuating means rod and piston 48 are translated into simultaneous and cooordinate pivotings and positionings relative frame it).

Pivot assemblies 72, best seen in FIGS. 3 and 4, are interconnected with the bottom ends of arms 40 of mechanisms 36 to effect pivotings and positionings thereof, and are mounted and supported inboard conveyors 28 by anchor plates 74 on the inner and upper flanges 29 thereof. Anchor plates 74 are fixed to flanges 29 by means of bolts 75 through elongate slots 77 therein, and may be adjusted positionally to the extent permitted by the length of slots 77. Pivotally mounted upon an upstanding flange portion 76 of plate 74 is a bell crank lever having a downwardly depending long arm 78 of the same length as lever 68 and the distance on lever 56 between its rotational axes with sleeve 62 and control shaft 66, and a laterally extending short arm 80, said pivotal mounting being effected by a bearing 83 and a joining stub shaft 82 passing therethrough. The lower end of long arm 78 is pivotally connected with control shaft 70 (or on the other side of machine 10 with control shaft 66, not here shown) for relative pivotal movement thereof through a stub shaft 84. The outer end of crank arm in turn is joined to the upper end of a downwardly disposed linkage arm 86 by means of a ball joint 88 and a bolt 89 passing therethrough, to permit relative pivotal and limited tilting movement therebetween. At the lower end 90 of linkage arm 86 interconnection is provided, by means of a ball joint 92 and a through-bolt 91, with the inwardly directed end portion 94- of a pivot lever 96 (as best seen in FIG. 6), so as to permit relative pivotal and limited tilting movement therebetween. Proximal the outer end H00 of pivot lever 96 interconnection is made with the bifurcate portions of the bottom of arm 49 of mechanism 36 by means of a joining shaft 102 extending therebetween and therethrough, which interconnection permits longitudinal pivotings of arm 40 during scissors movements of mechanism 36 and provides for coordinate pivotings of arm 40 and mechanism 36 with pivotings of pivot lever 96 about the axis of rod 42, pivot lever 96 being fixed at boss 98 thereof to the upper outer flange 29 of conveyor 28, not otherwise shown, for such relative rotation of lever 96.

OPERATION OF THE INVENTION A control system C, symbollically indicated in FIG. 2 by a black box marked C, is employed to control the actuation and deactuation, their timing and sequencing, of the various functional assemblies and components of automatic doffer 22 in effecting the hereinbefore described steps performed in the doffing and donning process. Control system C may be of any type known in the art to effect such control, such for example as those disclosed in aforesaid U.S. Pat. Nos. 3,786,621 and 3,751,895. At appropriate times when pivotings of grasper bars 24 are required, such as in described steps (j), (p), a w tem C will signal the actuating means to actuate pivotings of all lifter mechanisms 36 and their interconnected grasper bars 24, as now shall be described, in example, using the preferred embodiment to move grasper bars 24 toward machine 10 as in step (r) hereinbefore described.

Upon signal from system C, hydraulic fluid is caused to flow into and out of cylinder 46, as indicated by arrows in FIG. 2, to displace piston and rod 48 a prescribed distance to the right in the view shown, thus causing clevis 52 to pivot lever arm 56, rotate sleeve 62 and pivot other lever arm 68 through a prescribed angle in a counterclockwise direction. In so doing, interconnected control shafts 66 and 70 are moved longitudinal frame 10 to the right and raised precise distances, as symbollically indicated by arrows thereon in FIG. 3. Such movement of shafts 66 and 70 in turn rotate bell crank arms 78 and 80 through a precise angle in a counterclockwise direction in the view shown, about the axis each of their respective pivot points on shafts 82 of the plurality of assemblies 72 on both sides of frame 10. Such rotation of crank arms 78 displace linkage arms 86 downward through a precise chordal distance, and in turn causes rotation of pivot levers (FIG. 4) 96 clockwise in the view shown about the axis of respective rod 42 on both sides of frame 10 through a prescribed precise angle. Rotation of pivot levers 96 in turn rotates the bottom ends of arms 40 of all mechanisms 36, and through middle pivots 3 causes rotation of long arms 38 and grasper bars 24 connected therewith toward machine 10, aligning the grasper bars above their respective rows of spindles in accordance with step (r).

In the initial erection of the present doffing apparatus, although the aforesaid precise and predetermined distances and angles have been prescribed in manufacture of apparatus 22 through specification of exact lengths, contours, properties and interconnections of the components thereof, it has been found that however precise and exacting such manufacture and erection may be, one still does not attain the degree of exactitude required to assure that at step (r) the grasper bars will always be aligned precisely parallel a line normal to and intersecting the vertical axes of the spindle blades in a row thereof. Further, even were one to attain such initial alignment, it has been found that in time and with repeated cycling of the apparatus, even slight wear of the interconnections will cause misalignments such as skewing of or non-linearity in the grasper bars due say to imbalances of force being applied at their diverse points of interconnection with mechanisms 36. To obviate these difficulties, this invention provides, in combination with means for coordinate pivoting and positioning, means for adjusting the exact inward position of each grasper bar at each diverse point of interconnection with its associated mechanism 36 and an exact balance of forces at such points to assure exact linearity and parallelism as defined for the grasper bars.

Once apparatus 22 is erected and cycled through to step (r), it is stopped such that the grasper bars 24 are aligned inward machine 10 and over their respective rows of spindles; the parallelism as hereinbefore defined is measured to assure that each grasper element 26 is vertically coaxial with its corresponding spindle blade. Where skewing or non-linearity occurs, corresponding proximal anchor plates 74 are repositioned relative their anchor bolts 75 in slots 77 to adjust the positions of corresponding portions of bars 24 into linearity and parallelism. The same procedure is also followed later if malfunctions of apparatus 22 occur due to misalignments at step (r). It will be readily appreciated that when one shifts the position of anchor plate 74 one shifts the pivot point of bell crank lever arm and commensurately changes the chordal distance and displacement of linkage arm 86 thus shifting through pivot lever 96 and mechanism 36 the inward position of that portion of grasper bar 24 associated with such mechanism 36. Such appropriate adjustments of anchor plates 74 therefore simply and reliably restore exact parallelism to grasper bars 24 and vertical coaxial alignments of grasper elements 26 with their corresponding spindle blades.

Having thus disclosed the principles of the present invention in conjunction with a preferred embodiment and its operation, one knowledgeable in the art may readily appreciate such variations from that here told, such as functionally equivalent components, subassemblies and contours and interconnections, which will achieve the present objects of the invention and fall within the scope of the claims appended hereto.

We claim:

1. In an automatic doffer apparatus associated with a textile yarn processing machine having two rows of spindles on either side thereof, said apparatus having a grasper bar corresponding to each of said rows supported for raising and lowering and for lateral movement toward and away relative the machine and said rows by pivotable straight-line motion mechanisms interconnected each at spaced diverse points on said grasper bars longitudinal thereof, the improvement comprising:

actuating means for pivoting and positioning both grasper bars coordinately and simultaneously laterally relative said machine and said rows;

control means for controlling said actuating means to provide a precise and predetermined linear movement thereof;

and translating means for translating said linear movement into a precise angular pivoting of a pair of opposing levers on either side of said machine and said pivoting into a precise linear movement of a pair of control shafts on either side of said machine, and for translating said second linear movement into another precise angular pivoting of all of said straight-line motion mechanisms and their associated grasper bars relative said rows to a precise relative positioning thereto.

2. The improvement as in claim I further comprising adjustment means for adjusting said translating means to effect adjustment of said relative positioning of said grasper bars.

3. The improvement as in claim 2, wherein said translating means includes a plurality of bell crank levers corresponding to said plurality of straight-line motion mechanisms interconnected therewith for effecting translation of said linear movement of said control shafts into said pivoting movement thereof, and said adjusting means comprises a corresponding plurality of longitudinally adjustable anchor plates to which said bell crank levers are attached at their pivot points whereby positional adjustment of said plates correspondingly positionally adjusts said pivot points and shafts into said pivoting movement thereof.

5. The improvement as in claim 4, wherein said bell crank levers are fixed for pivoting at their pivot points to anchor plates which in turn are adjustably fixed to a rigid member of said apparatus for longitudinal displacement of said pivot points relative said machine. 

1. In an automatic doffer apparatus associated with a textile yarn processing machine having two rows of spindles on either side thereof, said apparatus having a grasper bar corresponding to each of said rows supported for raising and lowering and for lateral movement toward and away relative the machine and said rows by pivotable straight-line motion mechanisms interconnected each at spaced diverse points on said grasper bars longitudinal thereof, the improvement comprising: actuating means for pivoting and positioning both grasper bars coordinately and simultaneously laterally relative said machine and said rows; control means for controlling said actuating means to provide a precise and predetermined linear movement thereof; and translating means for translating said linear movement into a precise angular pivoting of a pair of opposing levers on either side of said machine and said pivoting inTo a precise linear movement of a pair of control shafts on either side of said machine, and for translating said second linear movement into another precise angular pivoting of all of said straightline motion mechanisms and their associated grasper bars relative said rows to a precise relative positioning thereto.
 2. The improvement as in claim 1 further comprising adjustment means for adjusting said translating means to effect adjustment of said relative positioning of said grasper bars.
 3. The improvement as in claim 2, wherein said translating means includes a plurality of bell crank levers corresponding to said plurality of straight-line motion mechanisms interconnected therewith for effecting translation of said linear movement of said control shafts into said pivoting movement thereof, and said adjusting means comprises a corresponding plurality of longitudinally adjustable anchor plates to which said bell crank levers are attached at their pivot points whereby positional adjustment of said plates correspondingly positionally adjusts said pivot points and said relative positioning of said grasper bars relative said machine and rows.
 4. The improvement as in claim 1, wherein said translating means includes a plurality of bell crank levers corresponding to said plurality of straight-line motion mechanisms interconnected therewith for effecting translation of said linear movement of said control shafts into said pivoting movement thereof.
 5. The improvement as in claim 4, wherein said bell crank levers are fixed for pivoting at their pivot points to anchor plates which in turn are adjustably fixed to a rigid member of said apparatus for longitudinal displacement of said pivot points relative said machine. 